Slight "hiss" when letting off accelerating past 4500 RPM
 

Hello everyone!

The engine is finally broken in, oil is refreshed, everything is going great.

I noticed this small "hissing" noise that seems to sound like a really quiet mini blow-off valve every time I accelerate into 4500 RPM territory and let off the throttle. I haven't ventured passed 5k RPM or WOT yet, still slowly working it in.

This only seems to happen at 75%+ throttle.

Everything checks out, sensors are all good, vacuum sensor shows near zero on throttle (0.2). It seems like there is a very small, almost inaudible hissing sound coming from the engine bay at idle.

The car is practically new, and the vacuum/air/intake lines all seem to be where they should be.

Looking for any thoughts on what it might be.

Thank you!

Hi ya, Prax ...... :)

If I recall proper, this "hiss" has been heard before.

You may wish to do a search.

If you car is stock, I would bet that the "hiss" is just the intake quickly "gasping/blowing off" ....... nothing to worry about.

Just another weird sound this engine makes ..... ;)


humfrz

The car is very stock. It probably is normal, just a new sound I am not used to. Thank you for the info, I will probably just have to get used to it.

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Just be careful when you open the hood.

http://i4.mirror.co.uk/incoming/arti...-728385636.jpg

Our engine is so loud! It's not even a "fast car" sound; more like the Engine is pushing hard as it can, to put a smile on our faces. lol

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Yep, sort of like an under powered tractor pulling a three bottom plow ......:D

Let's hear it from the old farm boys out there .......:cheers:


humfrz

My hiss got a bit louder after dropping in a K&N air filter. I think it's normal

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Deleting the sound tube removes this.

I might have to delete the sound tube, really wish they wouldn't engineer useless things like that.

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